hi,
I want to ask a question.
How to define a macro function that can be called by C language in armasm?
I know that in GNU can be used in the following way:
.macro push_x1_x12
push x1,x2
push x3,x4
push x5,x6
push x7,x8
push x9,x10
push x11,x12
.endm
ENTRY(test)
.......
push_x1_x12 ......ENDPROC(test)
Now in armasm, I used as follow :
MACRO
push_x1_x12
MEND
But how to expand the macro that can be called by C language??
In C language, you can define macros using the #DEFINE pre-processing command.
It will do text replacement before compiling.
Here is a documentation chapter explaining ARM Inline Assembly: ARM® Compiler armcc User Guide
Here is documentation about C preprocessor and #DEFINE: C preprocessor - Wikipedia, the free encyclopedia
#DEFINE push_x1_x12 \ __asm { \ push x1,x2 \ push x3,x4 \ push x5,x6 \ push x7,x8 \ push x9,x10 \ push x11,x12 \ }
thanks,
1、I used ARMV8 that platforms is: ARM DS-5 Documentation > ARM Compiler 6 (64-bit platforms only) > armclang Reference Guide
not armcc but armclang
2、how to expand in C language?like this:
void test_tt(void)
{
push_x1_x12;
}
3、If I want to define a macro with parameters, how to deal with it ?
Replace:
.macro cpus_tst_get_opcode, _reg0
lsl \_reg0,\_reg0,#4
lsr \_reg0,\_reg0,#24
albanrampon
2. Yes. The #define is identical to replacing the text.
3. You use parameters like for a function:
#define RADTODEG(x) ((x) * 57.29578)
and in your code
y = RADTODEG(25);
will do:
y = (25) * 57.29578;
sorry,
// define:
//-------------------------------------
#define push_x1_x12 \
__asm { \
push x1,x2 \
push x3,x4 \
push x5,x6 \
push x7,x8 \
push x9,x10 \
push x11,x12 \
// call
//----------------------------------------
ARM Compiler 6 Compilation error
javascript:liveAction('org.eclipse.help.ui', 'org.eclipse.help.ui.internal.ShowInTocAction', '2_4')
Oups, can you try the following?
#DEFINE push_x1_x12 __asm("push x1,x2", "push x1,x2", "push x3,x4", "push x5,x6", "push x7,x8", "push x9,x10", "push x11,x12")
6.4 Inline assembly language syntax with the __asm keyword in C and C++
The link just above also shows how to add parameters: you need to put them outside of the " " starting with #.
There are several ways of declaring assembly instructions. One at a time, or a list. And for the list, the way I explained previously with curly brackets "{}" or like strings in round brackets "()".
I am not sure why the curly brackets didn't work. It may depend on the compiler.
As described in the suggested by albanrampon to link section 6.4 Inline assembly language syntax with the __asm keyword in C and C++, the correct syntax is:
// define: //------------------------------------- #define push_x1_x12 \ __asm { \ "push x1,x2 \n" \ "push x3,x4 \n" \ "push x5,x6 \n" \ "push x7,x8 \n" \ "push x9,x10 \n" \ "push x11,x12 \n" \ } //call //---------------------------------------- void test_tt(void) { push_x1_x12; }
See lacked the quotes involving the mnemonics and the line break.